Many people suffer from pain in the joint located between the skull and the jaw. The joint is formed between the temporal bone of the skull and the mandible or jaw bone, and is commonly known as the temporo-mandibular joint or “TMJ”. The human body has two temporo-mandibular joints, one located on each side of the jaw in front of each ear. The TMJs move every time a person chews, talks, or swallows.
In greater detail, the TMJ is a paired joint articulating the mandibular condyle, articulator disc, and squamous portion of the temporal bone. The TMJ is capable of both glide and hinge movements. Specifically, the TMJ is formed by the mandibular condyle fitting into the mandibular fossa of the temporal bone. A separation of these two bones is accomplished by the articulator disc which is composed of dense fibrous connective tissue. Ligaments attach the articulator disc to the condyle, permitting rotational movement of the articulator disc during mouth opening and closure.
Displacement of the articulator disc introduces strain to the jaw muscles and causes muscle pain or fatigue around the jaw. In addition, articulator disc displacement often causes a painful clicking in the TMJ during certain jaw movements as the disc moves between normal and displaced positions. A number of other symptoms may occur as a result of a strained disc, including TMJ lock, shoulder, neck, and back pain, and headaches.
Conventional methods of treating temporo-mandibular joint disorders can be costly, physically cumbersome, involve invasive and irreversible treatment or be time consuming. Some conservative methods for treating TMJ discomfort include the use of an intra-oral splint, medication, and life style changes. One type of intra-oral splint is a stabilization apparatus which is used to help alter the posture of the mandible to a more open, relaxed, resting position. Another type of intra-oral splint is an anterior positioning apparatus. The anterior positioning apparatus attempts to decrease the compression load on the joint and alter the structural condyle disc relation. Both types of splints, however, cannot be used full time without risking displacement of teeth. Treatment by medication often involves the use of addictive drugs and/or anti-depressants and therefore can lead to misuse and abuse. In addition, medications often produce adverse side effects in the patient. Other conservative methods include chiropractic or physical therapy. Unfortunately, these methods require extensive time commitments and physical exertion by the patient.
More aggressive treatment of TMJ discomfort includes orthodontic treatment such as grinding down of teeth and various types of surgery. Orthodontic treatments, however, merely indirectly address TMJ pain by adjusting the dental articulation and overall bite of the patient. Furthermore, orthodontic approaches are invasive, irreversible, and expensive.
An alternative procedure and related apparatus for treatment of TMJ discomfort are disclosed in U.S. Pat. No. 5,769,891, the contents of which are incorporated by reference herein in their entirety. According to the disclosure in U.S. Pat. No. 5,769,891, a prosthesis is provided for insertion into the ear canal. The prosthesis has a rigid structural portion of a shape conforming to the ear canal when the jaw is in an open position. The prosthesis provides added support to the TMJ and associated secondary musculature to reduce strain in the TMJ area. In practice, this prosthesis is inserted into the ear canal with the jaw in either the open or closed position. Support is provided when the jaw is closed as the internal diameter of the ear canal is reduced. Another apparatus for treatment of TMJ discomfort is disclosed in U.S. patent application Ser. No. 12/075,046 (incorporated by reference). This apparatus likewise uses a substantially rigid structure providing support to the TMJ and associated secondary musculature.
Many people also suffer from severe headaches. In some instances, such headaches are related to defined TMJ disorders. In other cases, the headaches are not related to any discernable TMJ disorder. It has been found that the insertion of a substantially rigid prosthesis as disclosed in U.S. Pat. No. 5,769,891 and U.S. patent application Ser. No. 12/075,046 may provide relief for a sizeable percentage of people who suffer from headaches even where there is no discernable TMJ disorder. Without being limited to a specific theory, the present inventors believe that that support within the ear canal may reduce tension in surrounding muscles and ligaments, thereby relieving stress that may cause a tension headache.
While the prior rigid devices are believed to provide substantial benefits, they have to be sized for individual users or classes of users. Thus, a structure that is substantially self-adjusting for users of different sizes would be desirable.